Question

According to kübler-ross, when dying people feel sadness over future losses, know that death will bring an end to their relationships, know they will never see future generations, know death is inescapable, and experience a profound sense of sadness over the unalterable conclusion of their life, this is called

Answer 1

This is called preparatory depression.
In their preparation for upcoming death, these people become depressed and start looking back on their past. They realize that this is the end for them, that their life is really ending, and when faced with such realizations, many people start feeling depressed.